Metal container and method of making the same



'- March 24; 1936. w. R. ROBINSON METAL CONTAINER AND METHOD OF MAKINGTHE SAME Filed Jan. 4, 1 954 Patented Mar. 24, 1936 UNITED STATES METALCONTAINER AND METHOD OF MAKING THE SAME William R. Robinson, Niles, OhioApplication January 4, 1934, Serial No. 705,172

8 Claims.

This invention relates to improvements in metal containers and method ofmaking the same. It has to do particularly with ice cans which are sheetmetal' containers employed in connection with ice making apparatus forholding the water to be frozen. They are made of fairly heavy gaugesheet metal, generally galvanized steel, and are of rectangular form,being open at the top and closed at the bottom.

It is important that the cans be rust resisting to as great a degree aspossible. Rust in suspension in the water retards freezing time,discolors the ice and gives it an unpleasant taste, and in additioncauses the cans to deteriorate.

In accordance with the present invention I use a continuous welded jointon account of the manufacturing advantages which such a joint possessesin the way of economy and speed of production. While an overlapped jointmay be satisfactory and even desirable in some cases, I prefer as a ruleto use a butt joint. The welding heat tends to damage the galvanizingadjacent the seam, and the fin produced by the weld is of course devoidof any galvanizing. Hence, in

order to protect this portionof the can against rust it is necessary toapply to it some metallic coating which is resistant to rust. Thedipping of the can into molten metal for this purpose, after the weld ismade, tends to distort the metal of the can and produce buckling, which,in some cases, is of such extent as to interfere more or less with theremoval of the ice cakes, and furthermore detracts from the appearanceof the .l can and makes it unsalable on that account.

The precise reason for buckling is diflicult to ascertain, but it occursafter the corner of the can which includes the seam has been immersed inthe molten metal, the temperature of which may be several hundreddegrees Fahrenheit and varies with the character of the metal used. Thesudden raising of the temperature of this portion of the can and itssubsequent cooling appear to subject the metal to internal stresses, andthose stresses probably tend to produce a shortening or shrinkage of thetwo adjacent metal sheets at the butt seam and on both sides of thatseam.

I have discovered that a working of the metal at the welded, joint,after the weld is made and before the j int is dipped in molten solderor 50 other molten metal or alloy, overcomes the tendency to buckleheretofore mentioned. It is my belief that the working of the metal atthe joint tends to increase the length of the joint and thereforeprovides a condition prior to the shrinkage above referred to,'whichcompensates joint ice cans during their construction which shallsubstantially eliminate buckling in the side walls of the can.

Other objects and features of novelty will appear as I proceed with thedescription of those embodiments of the invention which, for the pur-,15

poses of the present application, I have illustrated in the accompaningdrawing, in which.

Fig. 1 is a perspective view of an ice can embodying the invention andbuilt in accordance with my improved method. 20

Fig. 2 is a fragmentary elevation showing one of the Welded joints inthe can.

Fig. 3 is a fragmentary cross sectional view on a larger scale, the viewbeing taken substantially on the line 3-3 of Fig. 2. 25

Fig. 4 is a similar view with the welding fin removed.

Figs. 5 and 6 are side end views, respectively, of a toothed rollerwhich may be employed for working the metal of the weld fin. 30

Figs. 7 and 8 are side and end views, respectively, of a plain'rollerwhich may be used for the same purpose, and

Figs. 9 and 10 are side and end views, respectively, of a roller with anannular groove therein 35 adapted to clear the weld fin and enable theapplication of pressure by the roller upon the can walls on either sideof the fin.

The side and end walls of the can are formed preferably of two sheets I0and II of galvanized 0 metal, the sheets being identical in size andjoined along their adjacent edges by seams l2. These seamsare butt seamsand the joint is made by welding. Any of the well known methodsofwelding butt joints of this character may be employed, although it maybe stated that for practical reasons I prefer electric welding to gaswelding.

In the welding operation there is thrown up along the outer side of thecan at each seam a fin l3 This fin does not present a ridge ofabsolutely uniform height and cross section, but its surface is somewhatwavy or uneven, For a reason which will presently appear, each of thetwo seams I 2 islocated quite close to the adjacent corner of the can.In practice I prefer to make this distance between the seam and thecorner three-fourths to seven-eighths of an inch. When the two seams I2have been welded, I place the open-ended, unfinished can upon anelongated anvil or bar of suitable form with one of the fins I3uppermost, and work the metal at the seam against such anvil in suchmanner as to lengthen the seam to a slight extent. This working isreferred to hereinafter as malleating, by which term I intend to includeany operation, such as rolling, which tends to alongate the seam, inother words any working of the metal which brings into play, or dependsfor its functioning upon, the malleability of the metal. In a can offorty-five inch depth, for example, the elongation at the seam may be ofthe order of threesixty-fourths of an inch. This elongation may beeffected in various ways, but I prefer to employ a roller I4, shown inFigs. 5 and 6, having teeth I5 therein, which roller is caused totraverse the fin I3 lengthwise under considerable pressure exertedagainst the anvil, whereby a series of transverse indentations I6 areimpressed into the fin, thereby elongating the same. Furthermore,-sincethe fin is an integral part of the can at the seam, the elongation ofthe fin also lengthens correspondingly the wall of the can at the seamand on either side thereof. A special machine of suitable design may beemployed for doing this work quickly and effectively. As soon as theroller has been caused to traverse one of the fins I3, the open-ended,unfinished can may be turned upon the anvil or bar support to bring theother fin I3 uppermost, when the operation is repeated.

In Figs. 7 and 8 I have illustrated a plain roller II which may beemployed instead of the toothed roller I4, sufficient pressure beingexerted by the roller upon the surface of the fin I3 and against thesupporting anvil to work the metal in the fin and elongate it togetherwith the metal of the can adjacent thereto.

The action of the roller I4 is somewhat more effective and certain thanthat of the smooth roller I1, and is to be preferred upon that accountin cases where the indentations I6 are not considered objectionable.

The roller I8 illustrated in Figs. 9 and 10 may also be employed ifdesired for elongating the metal of the can at the seam I2. In thisroller I provide an annular groove I9 of sufficient width and depth toreceive the fin I3 with clearance, so that the smooth surface of theroller on either side of the groove may bear upon the wall of the canadjacent the fin, and by the application of rolling pressure work themetal in such a way as to elongate the can wall adjacent the seam oneither side thereof, such elongation being necessarily imparted also tothe fin inasmuch as that is an integral part of the wall. A roller ofthis type of course does not deface the can in any way.

The application of the metal coating to the seams may be effected bymeans of any apparatus which will bring about direct contact of moltenmetal with at least the outside wall of the can along and adjacent tothe seams. I prefer to employ a trough as a container for the moltenmetal. I then support the can horizontally with one of the seam cornersdown, and dip it into the trough far enough to immerse both sides of theseam. The location of the seam close to the corner, as previouslydescribed, is an advantage, because the can may then be immersed a shortdistance only below the level of the molten liquid. The can is thenraised above the level of the liquid and inclined endwise to cause allexcess metal to flow off. It is then turned on its axis 5 and the othersteam is coated by the same procedure.

In cases where a can of particularly fine finish and appearance isdesired, I proceed in the following manner. The welds are made in theusual way, producing the fins I3 as previously stated, after which thefins are rolled with the toothed roller I4, producing the resultillustrated in Figs. 2 and 3, with the required elongation of the seam.Now, instead of proceeding at once to apply molten metal to the jointsfor protection against rust, I remove the indented fins I3 by somesuitable machining or grinding operation, leaving the joint plain andflush as shown in Fig. 4, after which the molten metal is caused to flowover the joints, inside and out. If preferred, a portion only of themetal of the fin may be removed, sufficient to efface the marks of thetoothed roller and to smooth up the wavy irregular appearance of thefin. I have discovered that the seams apparently retain the elongatedset given them by the rolling operation in spite of the removal of allor part of the fin, so that immersion of the joint in molten metalmerely takes out this preliminary distortion and leaves the metal of thecan at the seams free of strain and consequently free of any tendency tobuckle. This method or procedure produces a butt joint which is ofperfect appearance, devoid of any disfiguring marks, well protectedagainst rust, and entirely free of any tendency to buckle the metal ofthe can.

When the open-ended, unfinished can has been produced by my method inaccordance with one of the foregoing procedures, a reenforcing rim 20 iswelded or riveted to the upper edge of the can, and a bottom with anupturned flange ZI' is attached to the side walls by welding, orriveting, or otherwise. The lower end of the can is then dipped inmolten metal so as to protect the metal of the can at that seam againstrust and to seal the joint there, in case anyfurther sealing isnecessary.

While I prefer to apply molten solder to the seams and end joints of thecan as the rust resisting coating, other molten metals or alloys may besubstituted, molten zinc or molten tin being satisfactory for thepurpose in most instances.

Having thus described my invention, I claim:

1. The method of manufacturing a sheet metal can having a welded seam ina side wall thereof, which comprises welding the seam, elongating theseam to a slight extent by a rolling operation on the fin or bead formedby welding, and thereafter applying to the can upon and along the seammolten metal resistant to oxidation.

2. The method of manufacturing a sheet metal can having a continuouswelded butt seam in a side wall thereof, which comprises welding theseam, malleating the fin or bead produced by the weld, and applying tothe can along the seam molten metal resistant to oxidation.

3. The method of manufacturing a sheet metal can having a continuouswelded butt seam in a side wall thereof, which comprises welding theseam, elongating the fin produced by the weld, and applying to the canalong the seam molten metal resistant to oxidation.

4. The method of manufacturing a sheet metal can having a continuouswelded butt seam in a side wall thereof, which comprises welding theseam, malleating the fin produced by the weld, removing at least a.portion of the fin, and applying to the can upon and along the seammolten metal resistant to oxidation.

5. The method of manufacturing a sheet metal can having a continuouswelded butt seam in a side wall thereof, which comprises welding theseam, elongating the weld fin by indenting the same at intervals,removing metal from the fin to the extent at least of eliminating theindentations therein, and applying to the can along the seam moltenmetal resistant to oxidation.

6. The method of manufacturing a sheet metal can having a continuouswelded butt seam in a wall thereof, which comprises welding the seam,

elongating the weld by a rolling operation performed lengthwise of the'weld, and applying molten solder to the can upon and along said seam.

7. In a metal can, bottom and side walls, a side wall of the can havinga welded joint extending lengthwise of the can, the fin produced by theweld having transverse indentations therein, and the fin and the canadjacent thereto having a coating of metal resistant to oxidation.

8. In a metal can, bottom and side walls, a side wall of the can havinga welded joint therein extending longitudinally of the can close to onecorner thereof, the fin produced by the weld having transverseindentations therein, and the fin and the can adjacent thereto having acoating of metal resistant to oxidation.

WILLIAM R. ROBINSON.

